Spherical mesocellular silica foams: a superior support for hydrodesulfurization of fluid catalytic cracking diesel

Abstract

High surface area aluminum containing spherical mesocellular silica foams (SMCFs) with ultra-large pore volume and 3D pore size were successfully synthesized through a simple hydrothermal route, and the as-synthesized aluminum containing SMCFs (Al-SMCFs) was applied as the support of NiMo-base catalyst for the hydrodesulfurization (HDS) of fluid catalytic cracking (FCC) diesel. The as-synthesized supports and corresponding catalysts were characterized by powder small X-ray diffraction, nitrogen physisorption, scanning electron microscopy, transmission electron microscopy (TEM), inductively coupled plasma optical emission spectroscopy, and temperature-programmed reduction with H₂. The characterization results showed that, compared with other prepared catalysts (NiMo/Al-SBA-15 and NiMo/Al-KIT-6), the NiMo/Al-SMCFs catalyst possessed the most optimal physicochemical parameters, i.e., ultra-large 3D pore size (42.0 nm), high surface area (330.1 m²·g⁻¹), and ultra-large pore volume (1.96 cm³·g⁻¹), resulting in the formation of more homogeneous distribution of octahedral Mo active species and good mass transfer performance. Consequently, the NiMo/Al-SMCFs catalyst displayed the outstanding HDS performance (98.8%) of FCC diesel, confirming that the Al-SMCFs may be a type of promising candidate for oil hydrotreating.